Airfoil structure



' AIRFOIL STRUCTURE Filed yJune 6, 1944 S'SheetS-Sheet l Sept. 9, 1947. R. j. 'Nr-:Bl-:sAR

AIRFOIL STRUCTURE Filed June 6, 1944 5 Sheets-Sheef; 2

W/WESS: @IMM Sept. 9, 1947'.

R. ,1. NEBESAR AIRFOIL S TRUCTURE Filed'June 6, 1944 3 Sheets-Sheet 5 Patented Sept. 9, 1947 `vUfNI'I'lED S TAT ES OFF FICE ,2,427,0654

'AIRFOIL STRUCTURE Robert 1J. iNebesar, L'Bristol, Va., assigner ,.toiUxil-V sversal `Moulded fProductsCor-,p citation, Bristol,

Va.,` a corporation of Delaware Application June 6, 1944, Serialldd-"538,945

`fieGlairms. `l This invention relates f to i an improvement I in airfoil structurefandmore vparticularly relates.' to a novel-structurefor-wings, control surfaces, `and the like, for airplanes.

y'I-Ieretoforeairfoils, Yas wings, control.` surfaces, i,

and the like,havebeen.constructedby theiassemblyfof` a large numberfof `detailed .partswof intricate designrequiring for `their, construction and-assembly a `large number of-man hours. Further, as `heretofore rconstructed, 'such structures vhave required expensive materials in order r to minimize weight land :the resultant structures have not presented-smoothaerodynamic surfaces and, underfhig'h'vloading, their `skins havestended to wrinkle.

' lNow it is .theobjectoi` this invention to provide an airfoil structurei'whichvwill comprise 4azgreatly reduced number of parts', whichrwillbeduickly formed-and assembled, which will present smooth aerodynamic surfaces and which will present a skin proof against .'wrinkling.

The structure in accordance with this inventionrwill, in addition tofthe advantages of fewer parts and ease and speed of assembly, lend itself to production from inexpensive material, as, for example, any fibrous material, such as iibre glass, fabric, paper, or any other type of material, as wood; which, suitably impregnated, may be laminated. Y

Having'now indicated, in'ageneral way,` the nature-and purpose of this invention, I willfproceed i to -a detailed description `ofV preferred embodiments thereof, with 'reference to the `accompanying-drawings,- i-n which: Y

yFigure-1 isV aperspectivevview of a wingypartly broken away.

Figure 2 is an' exploded View, partly in section and partly broken away, showing the elements .composing the wing shown in Figure 1.

Figure `3 is a partial'sectional view oithewing shown in Figure 1.

Figure 4 is a sectional view showing a detail of construction.

Figure 5 is an exploded View, partly in section, showing a modification of the structure shown in Figure 1.

Figures 6 and '7 are sectional views showing details of construction of the structure shown in Figure 5.

Figure 8 is an exploded View, partly in section. showing a further modication of the structure shown in Figure l.

Figures 9, 10 and 11 are sectional views showing details of construction of the structure shown ln Figure 8.

lReferringfmore' particularlyftoFiguresA 1-4, the Wing shovvnlin Figure 1 comprises :essentiallyia main skin* section A Laride-anose f skin section B. The nose section provides'a'leading =edgebfor the-wing :and the main-section; provides av trailing# edge Lfr.

The skin=sections-A andB Aare formedseparate- 1y, -by molding a= plurality of fplies 'of'A any material, asi indicated,A Awhich canbe' laminated to the shape -of the respective sections.

*In the "molding of ltherskin vsections,skin `stiileners cycandtrihfcaps d, d are formedfon the inner sideL of the f skin by molding, while a spar cape-is formed interiorly of the main-skin sectionr-adjacent its forward-end. Each ofsaid spar caps having i a-forwardly vextending 'flange `and an inwardly extending'- flange forming an=angu lar recess 'in-each capA for `the reception of `a sparWeb.

AvA `spar :Web fcomprising aflatzpanel isformed from any suitable laminat-ed1 material and is providediwithwedgesgl molded on itsl forward face; vand-rib-websl1@for the main and noseskins, respectively, `comprise nat panels `formed from laminated material. *The rib webs h, for the main skin section, have fstiieners i -molded Aat Ytheir forward`y ends, while the rib Webs-`z',fforV the ,nose skin section are tapered at theirrear ends for entryinto: thehwedgesiyonJ the spar web.V

` The forwardedgeportions v- `of the `mainskin section and fthe'rear 'edge' portions ofl the nose skin'are scarfed asiat "For-'theeassembly of '-theistructureshown in Figure-` 1,comprising` the-'partsshownI in Figure `2, 'thefrib `webs2h-fand spar web \f are assembled 'into thefniain` vskin-section W"Acw-ith glue, it'` being noted that` shear :connections are -made- `between `rib websh aridi the spar web flinl the "mainrskn -sectionfby'|` the provisionof lextravglui-ng surface at the end of the'rrib caps,f-as at -y,`Figure2;and the rib webs i are assembled, with glue into the nose skin section B. Then the two sections are brought together, with entry of the tapered ends of the rib webs i into the wedges g on the spar web f, as shown in detail by Figure 4, and'glued together through the joints e, z made by scarfed edge portions 1v, n: above and below the spar Web.

As will be observed, the rib webs h and the stiffeners c in the skin sections A and B are, when the sections are assembled, lined and related to the spar web f so that when the scarfed joints e, z are made, an integral structure, to all intents and purposes, is formed.

Having reference now to Figures 5-7, the structure` shown is essentially the same as that described above with reference to Figures 1-4, and like parts are given like reference characters. However, the nose skin section comprises an upper skin section B and a lower skin section B", the upper section being tapered at its forward edge portion b, as at k, and the lower section being provided with a wedge l at its forward edge. The sections B and B" are provided with integrally molded stiffeners c and rib caps d and are assembled, with glue, to the rib webs z', each in this case provided with a stiiener m, and together through the joint n (Figure 6) formed by the entry of the tapered edge portion 1c of section B into the wedge loi section A.

And further, the main section comprises an upper skin section A' and a lower skin section A", secured together by gluing the surfaces o, o formed on the inner faces of the skin sections at the trailing edge.

The skin sections forming the main and nose sections having been formed with the rib webs in place, the spar web being in place in the main section, the two sections are assembled together as described with reference to Figures 1-4.

With reference to Figures 8-11, the modified structure shown is similar to the structure shown in Figures -7 in that the main section comprises an upper skin section A and a lower skin section A and the nose section comprises upper and lower skin sections B and B". However, in this modification the main and nose skin sections are provided with inner skins p, r1 spaced by the stiieners c from the outer skins q, q and between the skins are sheets or sections s of low density filling material, such, for example, as balsa wood, cellulose acetate, or the like, which are bonded to the outer skins. The stiieners c are formed to provide flat gluing surfaces r for the gluing thereto of the inner skins 1D, 29.

` As will be appreciated, the above detailed description of this invention in Various modiiications is for illustrative purposes only, itbeing contemplated that Various Inodications in detail may be made within the principle of the invention and without departing from the scope of the claims appended hereto.

What I claim and desire to protect by Letters Patent is: l

1. An airfoil structure formed from laminated material and comprising a molded main skin section, a molded nose skin section, stiifeners molded in said skin sections, rib caps molded in said sections, spar caps molded in the main section Aadjacent the forward edge thereof, a spar web, wedges molded on a face of the spar web,

rib webs secured to the rib caps in said sections and said sections being joined by scarfed joints adjacent said spar web with the rear ends of the rib webs in the nose skin section entered in the wedges on a face of thespar web.

2. An airfoil structure formed from laminated material and comprising a molded main skin section, a molded nose skin section, the main section comprising upper and lower skin sections joined at the trailing edge of the section and the nose section comprising upper and lower skin sections joined at the leading edge of said sections, rib caps and stiffeners molded integrally with the upper and lower skin sections of said main and nose sections, spar caps molded intev grally in said upper and lower skin sections of 4. An airfoil structure formed from laminated material and comprising a molded main skin section, a molded nose skin section, spar caps molded in the main section, each having a forwardly extending flange and an inwardly extending iiange, a spar web having wedges molded on the forward face thereof, the spar web and wedges being seated within recesses formed by the for. wardly and inwardly extending flanges of the spar caps, rib webs in the nose section having tapered ends seated vbetween said wedges and scarfed joints between the forwardly extending flanges of the spar caps and the nose section joining said sections to the spar web.

ROBERT J. NEBESAR.

REFERENCES CITED The following references are of record in the le of thisY patent:

UNITED STATES PATENTS Number Name Date 1,396,971 Meyercord Nov. 15, 1921 2,267,330 Goss Dec. 23, 1941 1,854,396 Davis Apr. 19, 1932 2,337,007 Vidal et al. Dec, 14, 1943 2,348,316 Vidal et al May 9, 1944 1,342,664 Charles June 8, 1920 1,976,480 Carleton et al Oct. 9, 1934 FOREIGN PATENTS Number Country Date 497,623 Great Britain Dec. 21, 1938 

